This invention relates to paging telemetry systems, and particularly to an automated telemetry paging system that provides an on-site telemetry unit installed at a remote location for monitoring the status of selected equipment or process parameters and automatically communicating with selected remote telephone pager units to indicate the status of the monitored parameters and any unacceptable deviation therefrom.
In many industrial applications, especially where equipment and processes are located at remote geographical sites, it is not feasible to have maintenance personnel on site around the clock, yet it is necessary to monitor the operation of key equipment and process steps, including such items as pumps, generators, pipe line flow rates, pressures, level measurements, radio transmitting equipment, rotating equipment, mechanical flow and flow rates, temperatures and temperature limits, security and fire alarm systems, etc. The list of parameters and unacceptable deviations therefrom is almost inexhaustible.
There have been many systems designed for remote monitoring, ranging from monitoring at the remote site and radio telemetry communicating with a company central office to the more recent computer telemetry communications with central office, where maintenance or service personal would be dispatched when an alarm situation was detected. Most existing systems rely upon the central station concept where the primary mode of processing data involves a fixed central station computer which in turn imposes distinct limitations on "distributed" processing due to topological constraints imposed by any such central computer station configuration. In addition, such systems are elaborate and costly, often requiring expensive radio and/or computer transmitting and receiving equipment at both the remote site location and the central office monitoring station Further, time delays were often encountered at the central monitoring station in contacting supervisory and maintenance personnel due to using a separate telephone and/or paging communication system.
The automatic remote telemetry paging system herein disclosed obviates the need for central station computers by offering true remote distributed data processing means for allowing a broad range of topology choices in the communications system comprising a remote telemetry unit that can communicate directly with a human recipient through a pager or portable receiver and thereby redefine the central function locality in terms of the pagers which are in automatic direct communication with the remote site being monitored at all times.
Accordingly, one primary feature of the present invention is to provide a simple paging telemetry system that communicates directly over telephone lines to paging network equipment to designated pager units associated with selected supervisory and maintenance personnel.
Another feature of the present invention is to provide rapid wide area and repeated notification of an alarm situation to key personnel.
Still another feature of the present invention is to provide fully automatic dispatching of a coded pager message directly to key personnel via telephone paging units without central office intervention.
Yet another feature of the present invention is to provide a remote telemetry unit for on-site installation at the location for monitoring that requires only customer provided signals indicative of the parameter to be monitored, dedicated telephone lines and a source of electrical power.
Still another feature of the present invention is the use of VLSI digital logic and a machine code software program to keep the microprocessor memory requirements to a minimum.
Another feature of the present invention is the ability to stack alarms as they occur, even if a prior deviation alarm notification procedure has not yet been completed, and then provide alarm notification on a LIFO basis.
Yet another feature of this invention is the ability of the remote telemetry unit to transmit alarm messages and telemetry data to digital and alphanumeric display pager units.
Still another feature of the present invention is to provide automatic repeat dialing of selected pager numbers for insuring pager message delivery.
Yet another feature of the present invention is the provision of verification of the transmitted status message at the on-site remote telemetry unit.